lkml.org 
[lkml]   [2009]   [Mar]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] block: fix memory leak in bio_clone()
On Mon, Mar 09 2009, Martin K. Petersen wrote:
> Jens> The second bug is that it should be using its own bioset, as it is
> Jens> illegal to do multiple __GFP_WAIT allocations on a single mempool
> Jens> and always expect progress.
>
> So how do you propose I go about this?
>
> The original intent was to contain all the integrity blah inside the
> bio_set to make it completely transparent to the caller. That's why the
> bip mempool is hanging off of the bio_set. But obviously two bvecs are
> needed per bio, one to describe data and to describe the integrity
> buffer.
>
> Having two bvec mempools per bio_set seems icky. I guess what you are
> suggesting is that we could have a dedicated bio_integrity_set akin to
> the bio_split_pool. That removes the caller's option of passing a
> dedicated bio_set to the clone command, though. Will that have forward
> progress implications for stacking drivers?

I was just wondering why you wanted to pass the bio_set in to
bio_integrity_clone(), why would the caller care?

Even two mempools isn't that bad. You can reuse the slab of course, and
the mempool should only have a single entry preallocated. But I agree,
it should not be in the bio_set. A dedicated bio_set for the integrity
stuff would be the way to go, and that should provide you all the
forward progress guarantees you need.

--
Jens Axboe



\
 
 \ /
  Last update: 2009-03-09 20:23    [W:1.088 / U:0.012 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site